Antiplatelet Drugs; L3 (9-24-15)

Question 1

Aspirin

Answer 1

• MOA: COX inhibitor (IRREVERSIBLE; COX-1 and COX-2); (anti-platelet net effect; decrease platelet production of TxA2, a platelet activator/vasoconstrictor)
• ROA: oral
• Indications: arterial thrombosis–ACS (acute coronary syndrome) and stroke; (analgesia, anti-inflammatory, antipyretic)
• Side-effects: (GI) bleeding, gastric irritation
• (Contraindications: AVOID IN KIDS bc of REYE’S SYNDROME; use w/ caution in pts w/ known peptic ulcer disease)

Question 2

Clopidogrel

Answer 2

• MOA: ADP receptor inhibitor
• ROA: oral
• Indications: ACS (acute coronary syndrome), stroke, given after coronary artery stenting (to decrease risk of stent thrombosis)
• Side-effects: bleeding, TTP (thrombotic thrombocytopenic purpura–occlusion due to platelet aggregation)

Question 3

Prasugrel, Ticagrelor

Answer 3

• MOA: ADP receptor inhibitor (REVERSIBLE - ticagrelor; IRREVERSIBLE - prasugrel)
• ROA: oral
• Indications: ACS (acute coronary syndrome), in stent thrombosis
• Side-effects: bleeding

Question 4

~NSAIDs

Answer 4

• MOA: COX inhibitor
• ROA: oral
• Indications: various diseases
• Side-effects: bleeding

Question 5

Dipyridamole

Answer 5

• MOA: phosphodiesterase inhibitor (^ cAMP in platelets -> ^vascular tone)
• ROA: oral
• Indications: arterial thrombosis, stroke; (prophylaxis of thromboembolic events in pts with a hx of TIA–transient ischemic attack–or CVA–cerebrovascular accident or stroke)

-Side-effects: bleeding
(-Contraindications: use caution in pts w/ hypotension–may cause peripheral vasodilatation)

Question 6

~Cilostazol

Answer 6

• MOA: phosphodiesterase inhibitor (peripheral vasodilation)
• ROA: oral
• Indications: intermittent claudication
• Side-effects: hypotension

Question 7

Abciximab

Answer 7

• MOA: GP IIb/IIIa inhibitor (Fab fragment of a chimeric monoclonal Ab against the GP IIb/IIIa receptor)
• ROA: IV
• Indications: ACS (acute coronary syndrome)/PCI (percutaneous coronary intervention–AKA angioplasty with stent)

-Side-effects: **bleeding
(-Contraindications: active or recent internal bleeding, major surgery or trauma, decrease in platelets or bleeding disorder; history of CVA or known intracranial neoplasm, arteriovenous malformation, or aneurysm)

(*Note: long 1/2 life of 8-12hrs and is NOT renally cleared)

Question 8

Eptifibatide

Answer 8

• MOA: GP IIb/IIIa inhibitor (inhibits platelet aggregation)
• ROA: IV
• Indications: ACS (acute coronary syndrome)/PCI (percutaneous coronary intervention–AKA angioplasty with stent)

-Side-effects: **bleeding
(-Contraindications: active or recent internal bleeding, major surgery or trauma, decrease in platelets or bleeding disorder; history of CVA or known intracranial neoplasm, arteriovenous malformation, or aneurysm)

(*Note: short 1/2 life of 2 hrs and is RENALLY cleared)

Question 9

Tirofiban

Answer 9

• MOA: GP IIb/IIIa inhibitor (non-peptide small molecule mimic)
• ROA: IV
• Indications: ACS (acute coronary syndrome)/PCI (percutaneous coronary intervention–AKA angioplasty with stent)

-Side-effects: **bleeding
(-Contraindications: active or recent internal bleeding, major surgery or trauma, decrease in platelets or bleeding disorder; history of CVA or known intracranial neoplasm, arteriovenous malformation, or aneurysm)

Question 10

Monteleukast

Answer 10

• MOA: leukotriene receptor inhibitor
• ROA: oral
• Indications: allergic reaction; (chronic asthma maintenance therapy)
• Side-effects: hypotension, behavioral changes

Question 11

Zafirleukast

Answer 11

• MOA: leukotriene receptor inhibitor (LTD4 blocker)
• ROA: oral
• Indications: asthma (for chronic maintenance therapy, NOT acute attacks)
• Side-effects: hypotension; (Churg-Strauss syndrome)

Question 12

Zieuton

Answer 12

• MOA: lipoxygenase inhibitor
• ROA: oral
• Indications: asthma
• Side-effects: hypotension; (hepatotoxicity; drug interactions–can increase serum concentrations of theophylline and warfarin)